This file is indexed.

/usr/lib/python3.2/platform.py is in python3.2-minimal 3.2.3-0ubuntu3.8.

This file is owned by root:root, with mode 0o755.

The actual contents of the file can be viewed below.

   1
   2
   3
   4
   5
   6
   7
   8
   9
  10
  11
  12
  13
  14
  15
  16
  17
  18
  19
  20
  21
  22
  23
  24
  25
  26
  27
  28
  29
  30
  31
  32
  33
  34
  35
  36
  37
  38
  39
  40
  41
  42
  43
  44
  45
  46
  47
  48
  49
  50
  51
  52
  53
  54
  55
  56
  57
  58
  59
  60
  61
  62
  63
  64
  65
  66
  67
  68
  69
  70
  71
  72
  73
  74
  75
  76
  77
  78
  79
  80
  81
  82
  83
  84
  85
  86
  87
  88
  89
  90
  91
  92
  93
  94
  95
  96
  97
  98
  99
 100
 101
 102
 103
 104
 105
 106
 107
 108
 109
 110
 111
 112
 113
 114
 115
 116
 117
 118
 119
 120
 121
 122
 123
 124
 125
 126
 127
 128
 129
 130
 131
 132
 133
 134
 135
 136
 137
 138
 139
 140
 141
 142
 143
 144
 145
 146
 147
 148
 149
 150
 151
 152
 153
 154
 155
 156
 157
 158
 159
 160
 161
 162
 163
 164
 165
 166
 167
 168
 169
 170
 171
 172
 173
 174
 175
 176
 177
 178
 179
 180
 181
 182
 183
 184
 185
 186
 187
 188
 189
 190
 191
 192
 193
 194
 195
 196
 197
 198
 199
 200
 201
 202
 203
 204
 205
 206
 207
 208
 209
 210
 211
 212
 213
 214
 215
 216
 217
 218
 219
 220
 221
 222
 223
 224
 225
 226
 227
 228
 229
 230
 231
 232
 233
 234
 235
 236
 237
 238
 239
 240
 241
 242
 243
 244
 245
 246
 247
 248
 249
 250
 251
 252
 253
 254
 255
 256
 257
 258
 259
 260
 261
 262
 263
 264
 265
 266
 267
 268
 269
 270
 271
 272
 273
 274
 275
 276
 277
 278
 279
 280
 281
 282
 283
 284
 285
 286
 287
 288
 289
 290
 291
 292
 293
 294
 295
 296
 297
 298
 299
 300
 301
 302
 303
 304
 305
 306
 307
 308
 309
 310
 311
 312
 313
 314
 315
 316
 317
 318
 319
 320
 321
 322
 323
 324
 325
 326
 327
 328
 329
 330
 331
 332
 333
 334
 335
 336
 337
 338
 339
 340
 341
 342
 343
 344
 345
 346
 347
 348
 349
 350
 351
 352
 353
 354
 355
 356
 357
 358
 359
 360
 361
 362
 363
 364
 365
 366
 367
 368
 369
 370
 371
 372
 373
 374
 375
 376
 377
 378
 379
 380
 381
 382
 383
 384
 385
 386
 387
 388
 389
 390
 391
 392
 393
 394
 395
 396
 397
 398
 399
 400
 401
 402
 403
 404
 405
 406
 407
 408
 409
 410
 411
 412
 413
 414
 415
 416
 417
 418
 419
 420
 421
 422
 423
 424
 425
 426
 427
 428
 429
 430
 431
 432
 433
 434
 435
 436
 437
 438
 439
 440
 441
 442
 443
 444
 445
 446
 447
 448
 449
 450
 451
 452
 453
 454
 455
 456
 457
 458
 459
 460
 461
 462
 463
 464
 465
 466
 467
 468
 469
 470
 471
 472
 473
 474
 475
 476
 477
 478
 479
 480
 481
 482
 483
 484
 485
 486
 487
 488
 489
 490
 491
 492
 493
 494
 495
 496
 497
 498
 499
 500
 501
 502
 503
 504
 505
 506
 507
 508
 509
 510
 511
 512
 513
 514
 515
 516
 517
 518
 519
 520
 521
 522
 523
 524
 525
 526
 527
 528
 529
 530
 531
 532
 533
 534
 535
 536
 537
 538
 539
 540
 541
 542
 543
 544
 545
 546
 547
 548
 549
 550
 551
 552
 553
 554
 555
 556
 557
 558
 559
 560
 561
 562
 563
 564
 565
 566
 567
 568
 569
 570
 571
 572
 573
 574
 575
 576
 577
 578
 579
 580
 581
 582
 583
 584
 585
 586
 587
 588
 589
 590
 591
 592
 593
 594
 595
 596
 597
 598
 599
 600
 601
 602
 603
 604
 605
 606
 607
 608
 609
 610
 611
 612
 613
 614
 615
 616
 617
 618
 619
 620
 621
 622
 623
 624
 625
 626
 627
 628
 629
 630
 631
 632
 633
 634
 635
 636
 637
 638
 639
 640
 641
 642
 643
 644
 645
 646
 647
 648
 649
 650
 651
 652
 653
 654
 655
 656
 657
 658
 659
 660
 661
 662
 663
 664
 665
 666
 667
 668
 669
 670
 671
 672
 673
 674
 675
 676
 677
 678
 679
 680
 681
 682
 683
 684
 685
 686
 687
 688
 689
 690
 691
 692
 693
 694
 695
 696
 697
 698
 699
 700
 701
 702
 703
 704
 705
 706
 707
 708
 709
 710
 711
 712
 713
 714
 715
 716
 717
 718
 719
 720
 721
 722
 723
 724
 725
 726
 727
 728
 729
 730
 731
 732
 733
 734
 735
 736
 737
 738
 739
 740
 741
 742
 743
 744
 745
 746
 747
 748
 749
 750
 751
 752
 753
 754
 755
 756
 757
 758
 759
 760
 761
 762
 763
 764
 765
 766
 767
 768
 769
 770
 771
 772
 773
 774
 775
 776
 777
 778
 779
 780
 781
 782
 783
 784
 785
 786
 787
 788
 789
 790
 791
 792
 793
 794
 795
 796
 797
 798
 799
 800
 801
 802
 803
 804
 805
 806
 807
 808
 809
 810
 811
 812
 813
 814
 815
 816
 817
 818
 819
 820
 821
 822
 823
 824
 825
 826
 827
 828
 829
 830
 831
 832
 833
 834
 835
 836
 837
 838
 839
 840
 841
 842
 843
 844
 845
 846
 847
 848
 849
 850
 851
 852
 853
 854
 855
 856
 857
 858
 859
 860
 861
 862
 863
 864
 865
 866
 867
 868
 869
 870
 871
 872
 873
 874
 875
 876
 877
 878
 879
 880
 881
 882
 883
 884
 885
 886
 887
 888
 889
 890
 891
 892
 893
 894
 895
 896
 897
 898
 899
 900
 901
 902
 903
 904
 905
 906
 907
 908
 909
 910
 911
 912
 913
 914
 915
 916
 917
 918
 919
 920
 921
 922
 923
 924
 925
 926
 927
 928
 929
 930
 931
 932
 933
 934
 935
 936
 937
 938
 939
 940
 941
 942
 943
 944
 945
 946
 947
 948
 949
 950
 951
 952
 953
 954
 955
 956
 957
 958
 959
 960
 961
 962
 963
 964
 965
 966
 967
 968
 969
 970
 971
 972
 973
 974
 975
 976
 977
 978
 979
 980
 981
 982
 983
 984
 985
 986
 987
 988
 989
 990
 991
 992
 993
 994
 995
 996
 997
 998
 999
1000
1001
1002
1003
1004
1005
1006
1007
1008
1009
1010
1011
1012
1013
1014
1015
1016
1017
1018
1019
1020
1021
1022
1023
1024
1025
1026
1027
1028
1029
1030
1031
1032
1033
1034
1035
1036
1037
1038
1039
1040
1041
1042
1043
1044
1045
1046
1047
1048
1049
1050
1051
1052
1053
1054
1055
1056
1057
1058
1059
1060
1061
1062
1063
1064
1065
1066
1067
1068
1069
1070
1071
1072
1073
1074
1075
1076
1077
1078
1079
1080
1081
1082
1083
1084
1085
1086
1087
1088
1089
1090
1091
1092
1093
1094
1095
1096
1097
1098
1099
1100
1101
1102
1103
1104
1105
1106
1107
1108
1109
1110
1111
1112
1113
1114
1115
1116
1117
1118
1119
1120
1121
1122
1123
1124
1125
1126
1127
1128
1129
1130
1131
1132
1133
1134
1135
1136
1137
1138
1139
1140
1141
1142
1143
1144
1145
1146
1147
1148
1149
1150
1151
1152
1153
1154
1155
1156
1157
1158
1159
1160
1161
1162
1163
1164
1165
1166
1167
1168
1169
1170
1171
1172
1173
1174
1175
1176
1177
1178
1179
1180
1181
1182
1183
1184
1185
1186
1187
1188
1189
1190
1191
1192
1193
1194
1195
1196
1197
1198
1199
1200
1201
1202
1203
1204
1205
1206
1207
1208
1209
1210
1211
1212
1213
1214
1215
1216
1217
1218
1219
1220
1221
1222
1223
1224
1225
1226
1227
1228
1229
1230
1231
1232
1233
1234
1235
1236
1237
1238
1239
1240
1241
1242
1243
1244
1245
1246
1247
1248
1249
1250
1251
1252
1253
1254
1255
1256
1257
1258
1259
1260
1261
1262
1263
1264
1265
1266
1267
1268
1269
1270
1271
1272
1273
1274
1275
1276
1277
1278
1279
1280
1281
1282
1283
1284
1285
1286
1287
1288
1289
1290
1291
1292
1293
1294
1295
1296
1297
1298
1299
1300
1301
1302
1303
1304
1305
1306
1307
1308
1309
1310
1311
1312
1313
1314
1315
1316
1317
1318
1319
1320
1321
1322
1323
1324
1325
1326
1327
1328
1329
1330
1331
1332
1333
1334
1335
1336
1337
1338
1339
1340
1341
1342
1343
1344
1345
1346
1347
1348
1349
1350
1351
1352
1353
1354
1355
1356
1357
1358
1359
1360
1361
1362
1363
1364
1365
1366
1367
1368
1369
1370
1371
1372
1373
1374
1375
1376
1377
1378
1379
1380
1381
1382
1383
1384
1385
1386
1387
1388
1389
1390
1391
1392
1393
1394
1395
1396
1397
1398
1399
1400
1401
1402
1403
1404
1405
1406
1407
1408
1409
1410
1411
1412
1413
1414
1415
1416
1417
1418
1419
1420
1421
1422
1423
1424
1425
1426
1427
1428
1429
1430
1431
1432
1433
1434
1435
1436
1437
1438
1439
1440
1441
1442
1443
1444
1445
1446
1447
1448
1449
1450
1451
1452
1453
1454
1455
1456
1457
1458
1459
1460
1461
1462
1463
1464
1465
1466
1467
1468
1469
1470
1471
1472
1473
1474
1475
1476
1477
1478
1479
1480
1481
1482
1483
1484
1485
1486
1487
1488
1489
1490
1491
1492
1493
1494
1495
1496
1497
1498
1499
1500
1501
1502
1503
1504
1505
1506
1507
1508
1509
1510
1511
1512
1513
1514
1515
1516
1517
1518
1519
1520
1521
1522
1523
1524
1525
1526
1527
1528
1529
1530
1531
1532
1533
1534
1535
1536
1537
1538
1539
1540
1541
1542
1543
1544
1545
1546
1547
1548
1549
1550
1551
1552
1553
1554
1555
1556
1557
1558
1559
1560
1561
1562
1563
1564
1565
1566
1567
1568
1569
1570
1571
1572
1573
1574
1575
1576
1577
1578
1579
1580
1581
1582
1583
1584
1585
1586
1587
1588
1589
1590
1591
1592
1593
1594
1595
1596
1597
1598
1599
1600
1601
1602
1603
1604
1605
1606
1607
#! /usr/bin/python3.2

""" This module tries to retrieve as much platform-identifying data as
    possible. It makes this information available via function APIs.

    If called from the command line, it prints the platform
    information concatenated as single string to stdout. The output
    format is useable as part of a filename.

"""
#    This module is maintained by Marc-Andre Lemburg <mal@egenix.com>.
#    If you find problems, please submit bug reports/patches via the
#    Python bug tracker (http://bugs.python.org) and assign them to "lemburg".
#
#    Still needed:
#    * more support for WinCE
#    * support for MS-DOS (PythonDX ?)
#    * support for Amiga and other still unsupported platforms running Python
#    * support for additional Linux distributions
#
#    Many thanks to all those who helped adding platform-specific
#    checks (in no particular order):
#
#      Charles G Waldman, David Arnold, Gordon McMillan, Ben Darnell,
#      Jeff Bauer, Cliff Crawford, Ivan Van Laningham, Josef
#      Betancourt, Randall Hopper, Karl Putland, John Farrell, Greg
#      Andruk, Just van Rossum, Thomas Heller, Mark R. Levinson, Mark
#      Hammond, Bill Tutt, Hans Nowak, Uwe Zessin (OpenVMS support),
#      Colin Kong, Trent Mick, Guido van Rossum, Anthony Baxter
#
#    History:
#
#    <see CVS and SVN checkin messages for history>
#
#    1.0.7 - added DEV_NULL
#    1.0.6 - added linux_distribution()
#    1.0.5 - fixed Java support to allow running the module on Jython
#    1.0.4 - added IronPython support
#    1.0.3 - added normalization of Windows system name
#    1.0.2 - added more Windows support
#    1.0.1 - reformatted to make doc.py happy
#    1.0.0 - reformatted a bit and checked into Python CVS
#    0.8.0 - added sys.version parser and various new access
#            APIs (python_version(), python_compiler(), etc.)
#    0.7.2 - fixed architecture() to use sizeof(pointer) where available
#    0.7.1 - added support for Caldera OpenLinux
#    0.7.0 - some fixes for WinCE; untabified the source file
#    0.6.2 - support for OpenVMS - requires version 1.5.2-V006 or higher and
#            vms_lib.getsyi() configured
#    0.6.1 - added code to prevent 'uname -p' on platforms which are
#            known not to support it
#    0.6.0 - fixed win32_ver() to hopefully work on Win95,98,NT and Win2k;
#            did some cleanup of the interfaces - some APIs have changed
#    0.5.5 - fixed another type in the MacOS code... should have
#            used more coffee today ;-)
#    0.5.4 - fixed a few typos in the MacOS code
#    0.5.3 - added experimental MacOS support; added better popen()
#            workarounds in _syscmd_ver() -- still not 100% elegant
#            though
#    0.5.2 - fixed uname() to return '' instead of 'unknown' in all
#            return values (the system uname command tends to return
#            'unknown' instead of just leaving the field emtpy)
#    0.5.1 - included code for slackware dist; added exception handlers
#            to cover up situations where platforms don't have os.popen
#            (e.g. Mac) or fail on socket.gethostname(); fixed libc
#            detection RE
#    0.5.0 - changed the API names referring to system commands to *syscmd*;
#            added java_ver(); made syscmd_ver() a private
#            API (was system_ver() in previous versions) -- use uname()
#            instead; extended the win32_ver() to also return processor
#            type information
#    0.4.0 - added win32_ver() and modified the platform() output for WinXX
#    0.3.4 - fixed a bug in _follow_symlinks()
#    0.3.3 - fixed popen() and "file" command invokation bugs
#    0.3.2 - added architecture() API and support for it in platform()
#    0.3.1 - fixed syscmd_ver() RE to support Windows NT
#    0.3.0 - added system alias support
#    0.2.3 - removed 'wince' again... oh well.
#    0.2.2 - added 'wince' to syscmd_ver() supported platforms
#    0.2.1 - added cache logic and changed the platform string format
#    0.2.0 - changed the API to use functions instead of module globals
#            since some action take too long to be run on module import
#    0.1.0 - first release
#
#    You can always get the latest version of this module at:
#
#             http://www.egenix.com/files/python/platform.py
#
#    If that URL should fail, try contacting the author.

__copyright__ = """
    Copyright (c) 1999-2000, Marc-Andre Lemburg; mailto:mal@lemburg.com
    Copyright (c) 2000-2010, eGenix.com Software GmbH; mailto:info@egenix.com

    Permission to use, copy, modify, and distribute this software and its
    documentation for any purpose and without fee or royalty is hereby granted,
    provided that the above copyright notice appear in all copies and that
    both that copyright notice and this permission notice appear in
    supporting documentation or portions thereof, including modifications,
    that you make.

    EGENIX.COM SOFTWARE GMBH DISCLAIMS ALL WARRANTIES WITH REGARD TO
    THIS SOFTWARE, INCLUDING ALL IMPLIED WARRANTIES OF MERCHANTABILITY AND
    FITNESS, IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY SPECIAL,
    INDIRECT OR CONSEQUENTIAL DAMAGES OR ANY DAMAGES WHATSOEVER RESULTING
    FROM LOSS OF USE, DATA OR PROFITS, WHETHER IN AN ACTION OF CONTRACT,
    NEGLIGENCE OR OTHER TORTIOUS ACTION, ARISING OUT OF OR IN CONNECTION
    WITH THE USE OR PERFORMANCE OF THIS SOFTWARE !

"""

__version__ = '1.0.7'

import sys, os, re

### Globals & Constants

# Determine the platform's /dev/null device
try:
    DEV_NULL = os.devnull
except AttributeError:
    # os.devnull was added in Python 2.4, so emulate it for earlier
    # Python versions
    if sys.platform in ('dos','win32','win16','os2'):
        # Use the old CP/M NUL as device name
        DEV_NULL = 'NUL'
    else:
        # Standard Unix uses /dev/null
        DEV_NULL = '/dev/null'

### Platform specific APIs

_libc_search = re.compile(r'(__libc_init)'
                          '|'
                          '(GLIBC_([0-9.]+))'
                          '|'
                          '(libc(_\w+)?\.so(?:\.(\d[0-9.]*))?)', re.ASCII)

def libc_ver(executable=sys.executable,lib='',version='',

             chunksize=2048):

    """ Tries to determine the libc version that the file executable
        (which defaults to the Python interpreter) is linked against.

        Returns a tuple of strings (lib,version) which default to the
        given parameters in case the lookup fails.

        Note that the function has intimate knowledge of how different
        libc versions add symbols to the executable and thus is probably
        only useable for executables compiled using gcc.

        The file is read and scanned in chunks of chunksize bytes.

    """
    if hasattr(os.path, 'realpath'):
        # Python 2.2 introduced os.path.realpath(); it is used
        # here to work around problems with Cygwin not being
        # able to open symlinks for reading
        executable = os.path.realpath(executable)
    f = open(executable,'rb')
    binary = f.read(chunksize).decode('latin-1')
    pos = 0
    while 1:
        m = _libc_search.search(binary,pos)
        if not m:
            binary = f.read(chunksize).decode('latin-1')
            if not binary:
                break
            pos = 0
            continue
        libcinit,glibc,glibcversion,so,threads,soversion = m.groups()
        if libcinit and not lib:
            lib = 'libc'
        elif glibc:
            if lib != 'glibc':
                lib = 'glibc'
                version = glibcversion
            elif glibcversion > version:
                version = glibcversion
        elif so:
            if lib != 'glibc':
                lib = 'libc'
                if soversion and soversion > version:
                    version = soversion
                if threads and version[-len(threads):] != threads:
                    version = version + threads
        pos = m.end()
    f.close()
    return lib,version

def _dist_try_harder(distname,version,id):

    """ Tries some special tricks to get the distribution
        information in case the default method fails.

        Currently supports older SuSE Linux, Caldera OpenLinux and
        Slackware Linux distributions.

    """
    if os.path.exists('/var/adm/inst-log/info'):
        # SuSE Linux stores distribution information in that file
        distname = 'SuSE'
        for line in open('/var/adm/inst-log/info'):
            tv = line.split()
            if len(tv) == 2:
                tag,value = tv
            else:
                continue
            if tag == 'MIN_DIST_VERSION':
                version = value.strip()
            elif tag == 'DIST_IDENT':
                values = value.split('-')
                id = values[2]
        return distname,version,id

    if os.path.exists('/etc/.installed'):
        # Caldera OpenLinux has some infos in that file (thanks to Colin Kong)
        for line in open('/etc/.installed'):
            pkg = line.split('-')
            if len(pkg) >= 2 and pkg[0] == 'OpenLinux':
                # XXX does Caldera support non Intel platforms ? If yes,
                #     where can we find the needed id ?
                return 'OpenLinux',pkg[1],id

    if os.path.isdir('/usr/lib/setup'):
        # Check for slackware verson tag file (thanks to Greg Andruk)
        verfiles = os.listdir('/usr/lib/setup')
        for n in range(len(verfiles)-1, -1, -1):
            if verfiles[n][:14] != 'slack-version-':
                del verfiles[n]
        if verfiles:
            verfiles.sort()
            distname = 'slackware'
            version = verfiles[-1][14:]
            return distname,version,id

    return distname,version,id

_release_filename = re.compile(r'(\w+)[-_](release|version)', re.ASCII)
_lsb_release_version = re.compile(r'(.+)'
                                   ' release '
                                   '([\d.]+)'
                                   '[^(]*(?:\((.+)\))?', re.ASCII)
_release_version = re.compile(r'([^0-9]+)'
                               '(?: release )?'
                               '([\d.]+)'
                               '[^(]*(?:\((.+)\))?', re.ASCII)

# See also http://www.novell.com/coolsolutions/feature/11251.html
# and http://linuxmafia.com/faq/Admin/release-files.html
# and http://data.linux-ntfs.org/rpm/whichrpm
# and http://www.die.net/doc/linux/man/man1/lsb_release.1.html

_supported_dists = (
    'SuSE', 'debian', 'fedora', 'redhat', 'centos',
    'mandrake', 'mandriva', 'rocks', 'slackware', 'yellowdog', 'gentoo',
    'UnitedLinux', 'turbolinux')

def _parse_release_file(firstline):

    # Default to empty 'version' and 'id' strings.  Both defaults are used
    # when 'firstline' is empty.  'id' defaults to empty when an id can not
    # be deduced.
    version = ''
    id = ''

    # Parse the first line
    m = _lsb_release_version.match(firstline)
    if m is not None:
        # LSB format: "distro release x.x (codename)"
        return tuple(m.groups())

    # Pre-LSB format: "distro x.x (codename)"
    m = _release_version.match(firstline)
    if m is not None:
        return tuple(m.groups())

    # Unkown format... take the first two words
    l = firstline.strip().split()
    if l:
        version = l[0]
        if len(l) > 1:
            id = l[1]
    return '', version, id

_distributor_id_file_re = re.compile("(?:DISTRIB_ID\s*=)\s*(.*)", re.I)
_release_file_re = re.compile("(?:DISTRIB_RELEASE\s*=)\s*(.*)", re.I)
_codename_file_re = re.compile("(?:DISTRIB_CODENAME\s*=)\s*(.*)", re.I)

def linux_distribution(distname='', version='', id='',

                       supported_dists=_supported_dists,
                       full_distribution_name=1):

    """ Tries to determine the name of the Linux OS distribution name.

        The function first looks for a distribution release file in
        /etc and then reverts to _dist_try_harder() in case no
        suitable files are found.

        supported_dists may be given to define the set of Linux
        distributions to look for. It defaults to a list of currently
        supported Linux distributions identified by their release file
        name.

        If full_distribution_name is true (default), the full
        distribution read from the OS is returned. Otherwise the short
        name taken from supported_dists is used.

        Returns a tuple (distname,version,id) which default to the
        args given as parameters.

    """
    # check for the Debian/Ubuntu /etc/lsb-release file first, needed so
    # that the distribution doesn't get identified as Debian.
    try:
        etclsbrel = open("/etc/lsb-release", "rU")
        for line in etclsbrel:
            m = _distributor_id_file_re.search(line)
            if m:
                _u_distname = m.group(1).strip()
            m = _release_file_re.search(line)
            if m:
                _u_version = m.group(1).strip()
            m = _codename_file_re.search(line)
            if m:
                _u_id = m.group(1).strip()
        if _u_distname and _u_version:
            return (_u_distname, _u_version, _u_id)
    except (EnvironmentError, UnboundLocalError):
            pass

    try:
        etc = os.listdir('/etc')
    except os.error:
        # Probably not a Unix system
        return distname,version,id
    etc.sort()
    for file in etc:
        m = _release_filename.match(file)
        if m is not None:
            _distname,dummy = m.groups()
            if _distname in supported_dists:
                distname = _distname
                break
    else:
        return _dist_try_harder(distname,version,id)

    # Read the first line
    with open('/etc/'+file, 'r') as f:
        firstline = f.readline()
    _distname, _version, _id = _parse_release_file(firstline)

    if _distname and full_distribution_name:
        distname = _distname
    if _version:
        version = _version
    if _id:
        id = _id
    return distname, version, id

# To maintain backwards compatibility:

def dist(distname='',version='',id='',

         supported_dists=_supported_dists):

    """ Tries to determine the name of the Linux OS distribution name.

        The function first looks for a distribution release file in
        /etc and then reverts to _dist_try_harder() in case no
        suitable files are found.

        Returns a tuple (distname,version,id) which default to the
        args given as parameters.

    """
    return linux_distribution(distname, version, id,
                              supported_dists=supported_dists,
                              full_distribution_name=0)

class _popen:

    """ Fairly portable (alternative) popen implementation.

        This is mostly needed in case os.popen() is not available, or
        doesn't work as advertised, e.g. in Win9X GUI programs like
        PythonWin or IDLE.

        Writing to the pipe is currently not supported.

    """
    tmpfile = ''
    pipe = None
    bufsize = None
    mode = 'r'

    def __init__(self,cmd,mode='r',bufsize=None):

        if mode != 'r':
            raise ValueError('popen()-emulation only supports read mode')
        import tempfile
        self.tmpfile = tmpfile = tempfile.mktemp()
        os.system(cmd + ' > %s' % tmpfile)
        self.pipe = open(tmpfile,'rb')
        self.bufsize = bufsize
        self.mode = mode

    def read(self):

        return self.pipe.read()

    def readlines(self):

        if self.bufsize is not None:
            return self.pipe.readlines()

    def close(self,

              remove=os.unlink,error=os.error):

        if self.pipe:
            rc = self.pipe.close()
        else:
            rc = 255
        if self.tmpfile:
            try:
                remove(self.tmpfile)
            except error:
                pass
        return rc

    # Alias
    __del__ = close

def popen(cmd, mode='r', bufsize=-1):

    """ Portable popen() interface.
    """
    # Find a working popen implementation preferring win32pipe.popen
    # over os.popen over _popen
    popen = None
    if os.environ.get('OS','') == 'Windows_NT':
        # On NT win32pipe should work; on Win9x it hangs due to bugs
        # in the MS C lib (see MS KnowledgeBase article Q150956)
        try:
            import win32pipe
        except ImportError:
            pass
        else:
            popen = win32pipe.popen
    if popen is None:
        if hasattr(os,'popen'):
            popen = os.popen
            # Check whether it works... it doesn't in GUI programs
            # on Windows platforms
            if sys.platform == 'win32': # XXX Others too ?
                try:
                    popen('')
                except os.error:
                    popen = _popen
        else:
            popen = _popen
    if bufsize is None:
        return popen(cmd,mode)
    else:
        return popen(cmd,mode,bufsize)

def _norm_version(version, build=''):

    """ Normalize the version and build strings and return a single
        version string using the format major.minor.build (or patchlevel).
    """
    l = version.split('.')
    if build:
        l.append(build)
    try:
        ints = map(int,l)
    except ValueError:
        strings = l
    else:
        strings = list(map(str,ints))
    version = '.'.join(strings[:3])
    return version

_ver_output = re.compile(r'(?:([\w ]+) ([\w.]+) '
                         '.*'
                         '\[.* ([\d.]+)\])')

# Examples of VER command output:
#
#   Windows 2000:  Microsoft Windows 2000 [Version 5.00.2195]
#   Windows XP:    Microsoft Windows XP [Version 5.1.2600]
#   Windows Vista: Microsoft Windows [Version 6.0.6002]
#
# Note that the "Version" string gets localized on different
# Windows versions.

def _syscmd_ver(system='', release='', version='',

               supported_platforms=('win32','win16','dos','os2')):

    """ Tries to figure out the OS version used and returns
        a tuple (system,release,version).

        It uses the "ver" shell command for this which is known
        to exists on Windows, DOS and OS/2. XXX Others too ?

        In case this fails, the given parameters are used as
        defaults.

    """
    if sys.platform not in supported_platforms:
        return system,release,version

    # Try some common cmd strings
    for cmd in ('ver','command /c ver','cmd /c ver'):
        try:
            pipe = popen(cmd)
            info = pipe.read()
            if pipe.close():
                raise os.error('command failed')
            # XXX How can I suppress shell errors from being written
            #     to stderr ?
        except os.error as why:
            #print 'Command %s failed: %s' % (cmd,why)
            continue
        except IOError as why:
            #print 'Command %s failed: %s' % (cmd,why)
            continue
        else:
            break
    else:
        return system,release,version

    # Parse the output
    info = info.strip()
    m = _ver_output.match(info)
    if m is not None:
        system,release,version = m.groups()
        # Strip trailing dots from version and release
        if release[-1] == '.':
            release = release[:-1]
        if version[-1] == '.':
            version = version[:-1]
        # Normalize the version and build strings (eliminating additional
        # zeros)
        version = _norm_version(version)
    return system,release,version

def _win32_getvalue(key,name,default=''):

    """ Read a value for name from the registry key.

        In case this fails, default is returned.

    """
    try:
        # Use win32api if available
        from win32api import RegQueryValueEx
    except ImportError:
        # On Python 2.0 and later, emulate using winreg
        import winreg
        RegQueryValueEx = winreg.QueryValueEx
    try:
        return RegQueryValueEx(key,name)
    except:
        return default

def win32_ver(release='',version='',csd='',ptype=''):

    """ Get additional version information from the Windows Registry
        and return a tuple (version,csd,ptype) referring to version
        number, CSD level (service pack), and OS type (multi/single
        processor).

        As a hint: ptype returns 'Uniprocessor Free' on single
        processor NT machines and 'Multiprocessor Free' on multi
        processor machines. The 'Free' refers to the OS version being
        free of debugging code. It could also state 'Checked' which
        means the OS version uses debugging code, i.e. code that
        checks arguments, ranges, etc. (Thomas Heller).

        Note: this function works best with Mark Hammond's win32
        package installed, but also on Python 2.3 and later. It
        obviously only runs on Win32 compatible platforms.

    """
    # XXX Is there any way to find out the processor type on WinXX ?
    # XXX Is win32 available on Windows CE ?
    #
    # Adapted from code posted by Karl Putland to comp.lang.python.
    #
    # The mappings between reg. values and release names can be found
    # here: http://msdn.microsoft.com/library/en-us/sysinfo/base/osversioninfo_str.asp

    # Import the needed APIs
    try:
        import win32api
        from win32api import RegQueryValueEx, RegOpenKeyEx, \
             RegCloseKey, GetVersionEx
        from win32con import HKEY_LOCAL_MACHINE, VER_PLATFORM_WIN32_NT, \
             VER_PLATFORM_WIN32_WINDOWS, VER_NT_WORKSTATION
    except ImportError:
        # Emulate the win32api module using Python APIs
        try:
            sys.getwindowsversion
        except AttributeError:
            # No emulation possible, so return the defaults...
            return release,version,csd,ptype
        else:
            # Emulation using winreg (added in Python 2.0) and
            # sys.getwindowsversion() (added in Python 2.3)
            import winreg
            GetVersionEx = sys.getwindowsversion
            RegQueryValueEx = winreg.QueryValueEx
            RegOpenKeyEx = winreg.OpenKeyEx
            RegCloseKey = winreg.CloseKey
            HKEY_LOCAL_MACHINE = winreg.HKEY_LOCAL_MACHINE
            VER_PLATFORM_WIN32_WINDOWS = 1
            VER_PLATFORM_WIN32_NT = 2
            VER_NT_WORKSTATION = 1
            VER_NT_SERVER = 3
            REG_SZ = 1

    # Find out the registry key and some general version infos
    winver = GetVersionEx()
    maj,min,buildno,plat,csd = winver
    version = '%i.%i.%i' % (maj,min,buildno & 0xFFFF)
    if hasattr(winver, "service_pack"):
        if winver.service_pack != "":
            csd = 'SP%s' % winver.service_pack_major
    else:
        if csd[:13] == 'Service Pack ':
            csd = 'SP' + csd[13:]

    if plat == VER_PLATFORM_WIN32_WINDOWS:
        regkey = 'SOFTWARE\\Microsoft\\Windows\\CurrentVersion'
        # Try to guess the release name
        if maj == 4:
            if min == 0:
                release = '95'
            elif min == 10:
                release = '98'
            elif min == 90:
                release = 'Me'
            else:
                release = 'postMe'
        elif maj == 5:
            release = '2000'

    elif plat == VER_PLATFORM_WIN32_NT:
        regkey = 'SOFTWARE\\Microsoft\\Windows NT\\CurrentVersion'
        if maj <= 4:
            release = 'NT'
        elif maj == 5:
            if min == 0:
                release = '2000'
            elif min == 1:
                release = 'XP'
            elif min == 2:
                release = '2003Server'
            else:
                release = 'post2003'
        elif maj == 6:
            if hasattr(winver, "product_type"):
                product_type = winver.product_type
            else:
                product_type = VER_NT_WORKSTATION
                # Without an OSVERSIONINFOEX capable sys.getwindowsversion(),
                # or help from the registry, we cannot properly identify
                # non-workstation versions.
                try:
                    key = RegOpenKeyEx(HKEY_LOCAL_MACHINE, regkey)
                    name, type = RegQueryValueEx(key, "ProductName")
                    # Discard any type that isn't REG_SZ
                    if type == REG_SZ and name.find("Server") != -1:
                        product_type = VER_NT_SERVER
                except WindowsError:
                    # Use default of VER_NT_WORKSTATION
                    pass

            if min == 0:
                if product_type == VER_NT_WORKSTATION:
                    release = 'Vista'
                else:
                    release = '2008Server'
            elif min == 1:
                if product_type == VER_NT_WORKSTATION:
                    release = '7'
                else:
                    release = '2008ServerR2'
            else:
                release = 'post2008Server'

    else:
        if not release:
            # E.g. Win3.1 with win32s
            release = '%i.%i' % (maj,min)
        return release,version,csd,ptype

    # Open the registry key
    try:
        keyCurVer = RegOpenKeyEx(HKEY_LOCAL_MACHINE, regkey)
        # Get a value to make sure the key exists...
        RegQueryValueEx(keyCurVer, 'SystemRoot')
    except:
        return release,version,csd,ptype

    # Parse values
    #subversion = _win32_getvalue(keyCurVer,
    #                            'SubVersionNumber',
    #                            ('',1))[0]
    #if subversion:
    #   release = release + subversion # 95a, 95b, etc.
    build = _win32_getvalue(keyCurVer,
                            'CurrentBuildNumber',
                            ('',1))[0]
    ptype = _win32_getvalue(keyCurVer,
                           'CurrentType',
                           (ptype,1))[0]

    # Normalize version
    version = _norm_version(version,build)

    # Close key
    RegCloseKey(keyCurVer)
    return release,version,csd,ptype

def _mac_ver_lookup(selectors,default=None):

    from _gestalt import gestalt
    l = []
    append = l.append
    for selector in selectors:
        try:
            append(gestalt(selector))
        except (RuntimeError, OSError):
            append(default)
    return l

def _bcd2str(bcd):

    return hex(bcd)[2:]

def _mac_ver_gestalt():
    """
        Thanks to Mark R. Levinson for mailing documentation links and
        code examples for this function. Documentation for the
        gestalt() API is available online at:

           http://www.rgaros.nl/gestalt/
    """
    # Check whether the version info module is available
    try:
        import _gestalt
    except ImportError:
        return None
    # Get the infos
    sysv, sysa = _mac_ver_lookup(('sysv','sysa'))
    # Decode the infos
    if sysv:
        major = (sysv & 0xFF00) >> 8
        minor = (sysv & 0x00F0) >> 4
        patch = (sysv & 0x000F)

        if (major, minor) >= (10, 4):
            # the 'sysv' gestald cannot return patchlevels
            # higher than 9. Apple introduced 3 new
            # gestalt codes in 10.4 to deal with this
            # issue (needed because patch levels can
            # run higher than 9, such as 10.4.11)
            major,minor,patch = _mac_ver_lookup(('sys1','sys2','sys3'))
            release = '%i.%i.%i' %(major, minor, patch)
        else:
            release = '%s.%i.%i' % (_bcd2str(major),minor,patch)

    if sysa:
        machine = {0x1: '68k',
                   0x2: 'PowerPC',
                   0xa: 'i386'}.get(sysa,'')

    versioninfo=('', '', '')
    return release,versioninfo,machine

def _mac_ver_xml():
    fn = '/System/Library/CoreServices/SystemVersion.plist'
    if not os.path.exists(fn):
        return None

    try:
        import plistlib
    except ImportError:
        return None

    pl = plistlib.readPlist(fn)
    release = pl['ProductVersion']
    versioninfo=('', '', '')
    machine = os.uname()[4]
    if machine in ('ppc', 'Power Macintosh'):
        # for compatibility with the gestalt based code
        machine = 'PowerPC'

    return release,versioninfo,machine


def mac_ver(release='',versioninfo=('','',''),machine=''):

    """ Get MacOS version information and return it as tuple (release,
        versioninfo, machine) with versioninfo being a tuple (version,
        dev_stage, non_release_version).

        Entries which cannot be determined are set to the paramter values
        which default to ''. All tuple entries are strings.
    """

    # First try reading the information from an XML file which should
    # always be present
    info = _mac_ver_xml()
    if info is not None:
        return info

    # If that doesn't work for some reason fall back to reading the
    # information using gestalt calls.
    info = _mac_ver_gestalt()
    if info is not None:
        return info

    # If that also doesn't work return the default values
    return release,versioninfo,machine

def _java_getprop(name,default):

    from java.lang import System
    try:
        value = System.getProperty(name)
        if value is None:
            return default
        return value
    except AttributeError:
        return default

def java_ver(release='',vendor='',vminfo=('','',''),osinfo=('','','')):

    """ Version interface for Jython.

        Returns a tuple (release,vendor,vminfo,osinfo) with vminfo being
        a tuple (vm_name,vm_release,vm_vendor) and osinfo being a
        tuple (os_name,os_version,os_arch).

        Values which cannot be determined are set to the defaults
        given as parameters (which all default to '').

    """
    # Import the needed APIs
    try:
        import java.lang
    except ImportError:
        return release,vendor,vminfo,osinfo

    vendor = _java_getprop('java.vendor', vendor)
    release = _java_getprop('java.version', release)
    vm_name, vm_release, vm_vendor = vminfo
    vm_name = _java_getprop('java.vm.name', vm_name)
    vm_vendor = _java_getprop('java.vm.vendor', vm_vendor)
    vm_release = _java_getprop('java.vm.version', vm_release)
    vminfo = vm_name, vm_release, vm_vendor
    os_name, os_version, os_arch = osinfo
    os_arch = _java_getprop('java.os.arch', os_arch)
    os_name = _java_getprop('java.os.name', os_name)
    os_version = _java_getprop('java.os.version', os_version)
    osinfo = os_name, os_version, os_arch

    return release, vendor, vminfo, osinfo

### System name aliasing

def system_alias(system,release,version):

    """ Returns (system,release,version) aliased to common
        marketing names used for some systems.

        It also does some reordering of the information in some cases
        where it would otherwise cause confusion.

    """
    if system == 'Rhapsody':
        # Apple's BSD derivative
        # XXX How can we determine the marketing release number ?
        return 'MacOS X Server',system+release,version

    elif system == 'SunOS':
        # Sun's OS
        if release < '5':
            # These releases use the old name SunOS
            return system,release,version
        # Modify release (marketing release = SunOS release - 3)
        l = release.split('.')
        if l:
            try:
                major = int(l[0])
            except ValueError:
                pass
            else:
                major = major - 3
                l[0] = str(major)
                release = '.'.join(l)
        if release < '6':
            system = 'Solaris'
        else:
            # XXX Whatever the new SunOS marketing name is...
            system = 'Solaris'

    elif system == 'IRIX64':
        # IRIX reports IRIX64 on platforms with 64-bit support; yet it
        # is really a version and not a different platform, since 32-bit
        # apps are also supported..
        system = 'IRIX'
        if version:
            version = version + ' (64bit)'
        else:
            version = '64bit'

    elif system in ('win32','win16'):
        # In case one of the other tricks
        system = 'Windows'

    return system,release,version

### Various internal helpers

def _platform(*args):

    """ Helper to format the platform string in a filename
        compatible format e.g. "system-version-machine".
    """
    # Format the platform string
    platform = '-'.join(x.strip() for x in filter(len, args))

    # Cleanup some possible filename obstacles...
    platform = platform.replace(' ','_')
    platform = platform.replace('/','-')
    platform = platform.replace('\\','-')
    platform = platform.replace(':','-')
    platform = platform.replace(';','-')
    platform = platform.replace('"','-')
    platform = platform.replace('(','-')
    platform = platform.replace(')','-')

    # No need to report 'unknown' information...
    platform = platform.replace('unknown','')

    # Fold '--'s and remove trailing '-'
    while 1:
        cleaned = platform.replace('--','-')
        if cleaned == platform:
            break
        platform = cleaned
    while platform[-1] == '-':
        platform = platform[:-1]

    return platform

def _node(default=''):

    """ Helper to determine the node name of this machine.
    """
    try:
        import socket
    except ImportError:
        # No sockets...
        return default
    try:
        return socket.gethostname()
    except socket.error:
        # Still not working...
        return default

def _follow_symlinks(filepath):

    """ In case filepath is a symlink, follow it until a
        real file is reached.
    """
    filepath = os.path.abspath(filepath)
    while os.path.islink(filepath):
        filepath = os.path.normpath(
            os.path.join(os.path.dirname(filepath),os.readlink(filepath)))
    return filepath

def _syscmd_uname(option,default=''):

    """ Interface to the system's uname command.
    """
    if sys.platform in ('dos','win32','win16','os2'):
        # XXX Others too ?
        return default
    try:
        f = os.popen('uname %s 2> %s' % (option, DEV_NULL))
    except (AttributeError,os.error):
        return default
    output = f.read().strip()
    rc = f.close()
    if not output or rc:
        return default
    else:
        return output

def _syscmd_file(target,default=''):

    """ Interface to the system's file command.

        The function uses the -b option of the file command to have it
        omit the filename in its output. Follow the symlinks. It returns
        default in case the command should fail.

    """
    if sys.platform in ('dos','win32','win16','os2'):
        # XXX Others too ?
        return default
    target = _follow_symlinks(target).replace('"', '\\"')
    try:
        f = os.popen('file -b "%s" 2> %s' % (target, DEV_NULL))
    except (AttributeError,os.error):
        return default
    output = f.read().strip()
    rc = f.close()
    if not output or rc:
        return default
    else:
        return output

### Information about the used architecture

# Default values for architecture; non-empty strings override the
# defaults given as parameters
_default_architecture = {
    'win32': ('','WindowsPE'),
    'win16': ('','Windows'),
    'dos': ('','MSDOS'),
}

def architecture(executable=sys.executable,bits='',linkage=''):

    """ Queries the given executable (defaults to the Python interpreter
        binary) for various architecture information.

        Returns a tuple (bits,linkage) which contains information about
        the bit architecture and the linkage format used for the
        executable. Both values are returned as strings.

        Values that cannot be determined are returned as given by the
        parameter presets. If bits is given as '', the sizeof(pointer)
        (or sizeof(long) on Python version < 1.5.2) is used as
        indicator for the supported pointer size.

        The function relies on the system's "file" command to do the
        actual work. This is available on most if not all Unix
        platforms. On some non-Unix platforms where the "file" command
        does not exist and the executable is set to the Python interpreter
        binary defaults from _default_architecture are used.

    """
    # Use the sizeof(pointer) as default number of bits if nothing
    # else is given as default.
    if not bits:
        import struct
        try:
            size = struct.calcsize('P')
        except struct.error:
            # Older installations can only query longs
            size = struct.calcsize('l')
        bits = str(size*8) + 'bit'

    # Get data from the 'file' system command
    if executable:
        fileout = _syscmd_file(executable, '')
    else:
        fileout = ''

    if not fileout and \
       executable == sys.executable:
        # "file" command did not return anything; we'll try to provide
        # some sensible defaults then...
        if sys.platform in _default_architecture:
            b,l = _default_architecture[sys.platform]
            if b:
                bits = b
            if l:
                linkage = l
        return bits,linkage

    if 'executable' not in fileout:
        # Format not supported
        return bits,linkage

    # Bits
    if '32-bit' in fileout:
        bits = '32bit'
    elif 'N32' in fileout:
        # On Irix only
        bits = 'n32bit'
    elif '64-bit' in fileout:
        bits = '64bit'

    # Linkage
    if 'ELF' in fileout:
        linkage = 'ELF'
    elif 'PE' in fileout:
        # E.g. Windows uses this format
        if 'Windows' in fileout:
            linkage = 'WindowsPE'
        else:
            linkage = 'PE'
    elif 'COFF' in fileout:
        linkage = 'COFF'
    elif 'MS-DOS' in fileout:
        linkage = 'MSDOS'
    else:
        # XXX the A.OUT format also falls under this class...
        pass

    return bits,linkage

### Portable uname() interface

_uname_cache = None

def uname():

    """ Fairly portable uname interface. Returns a tuple
        of strings (system,node,release,version,machine,processor)
        identifying the underlying platform.

        Note that unlike the os.uname function this also returns
        possible processor information as an additional tuple entry.

        Entries which cannot be determined are set to ''.

    """
    global _uname_cache
    no_os_uname = 0

    if _uname_cache is not None:
        return _uname_cache

    processor = ''

    # Get some infos from the builtin os.uname API...
    try:
        system,node,release,version,machine = os.uname()
    except AttributeError:
        no_os_uname = 1

    if no_os_uname or not list(filter(None, (system, node, release, version, machine))):
        # Hmm, no there is either no uname or uname has returned
        #'unknowns'... we'll have to poke around the system then.
        if no_os_uname:
            system = sys.platform
            release = ''
            version = ''
            node = _node()
            machine = ''

        use_syscmd_ver = 1

        # Try win32_ver() on win32 platforms
        if system == 'win32':
            release,version,csd,ptype = win32_ver()
            if release and version:
                use_syscmd_ver = 0
            # Try to use the PROCESSOR_* environment variables
            # available on Win XP and later; see
            # http://support.microsoft.com/kb/888731 and
            # http://www.geocities.com/rick_lively/MANUALS/ENV/MSWIN/PROCESSI.HTM
            if not machine:
                # WOW64 processes mask the native architecture
                if "PROCESSOR_ARCHITEW6432" in os.environ:
                    machine = os.environ.get("PROCESSOR_ARCHITEW6432", '')
                else:
                    machine = os.environ.get('PROCESSOR_ARCHITECTURE', '')
            if not processor:
                processor = os.environ.get('PROCESSOR_IDENTIFIER', machine)

        # Try the 'ver' system command available on some
        # platforms
        if use_syscmd_ver:
            system,release,version = _syscmd_ver(system)
            # Normalize system to what win32_ver() normally returns
            # (_syscmd_ver() tends to return the vendor name as well)
            if system == 'Microsoft Windows':
                system = 'Windows'
            elif system == 'Microsoft' and release == 'Windows':
                # Under Windows Vista and Windows Server 2008,
                # Microsoft changed the output of the ver command. The
                # release is no longer printed.  This causes the
                # system and release to be misidentified.
                system = 'Windows'
                if '6.0' == version[:3]:
                    release = 'Vista'
                else:
                    release = ''

        # In case we still don't know anything useful, we'll try to
        # help ourselves
        if system in ('win32','win16'):
            if not version:
                if system == 'win32':
                    version = '32bit'
                else:
                    version = '16bit'
            system = 'Windows'

        elif system[:4] == 'java':
            release,vendor,vminfo,osinfo = java_ver()
            system = 'Java'
            version = ', '.join(vminfo)
            if not version:
                version = vendor

    # System specific extensions
    if system == 'OpenVMS':
        # OpenVMS seems to have release and version mixed up
        if not release or release == '0':
            release = version
            version = ''
        # Get processor information
        try:
            import vms_lib
        except ImportError:
            pass
        else:
            csid, cpu_number = vms_lib.getsyi('SYI$_CPU',0)
            if (cpu_number >= 128):
                processor = 'Alpha'
            else:
                processor = 'VAX'
    if not processor:
        # Get processor information from the uname system command
        processor = _syscmd_uname('-p','')

    #If any unknowns still exist, replace them with ''s, which are more portable
    if system == 'unknown':
        system = ''
    if node == 'unknown':
        node = ''
    if release == 'unknown':
        release = ''
    if version == 'unknown':
        version = ''
    if machine == 'unknown':
        machine = ''
    if processor == 'unknown':
        processor = ''

    #  normalize name
    if system == 'Microsoft' and release == 'Windows':
        system = 'Windows'
        release = 'Vista'

    _uname_cache = system,node,release,version,machine,processor
    return _uname_cache

### Direct interfaces to some of the uname() return values

def system():

    """ Returns the system/OS name, e.g. 'Linux', 'Windows' or 'Java'.

        An empty string is returned if the value cannot be determined.

    """
    return uname()[0]

def node():

    """ Returns the computer's network name (which may not be fully
        qualified)

        An empty string is returned if the value cannot be determined.

    """
    return uname()[1]

def release():

    """ Returns the system's release, e.g. '2.2.0' or 'NT'

        An empty string is returned if the value cannot be determined.

    """
    return uname()[2]

def version():

    """ Returns the system's release version, e.g. '#3 on degas'

        An empty string is returned if the value cannot be determined.

    """
    return uname()[3]

def machine():

    """ Returns the machine type, e.g. 'i386'

        An empty string is returned if the value cannot be determined.

    """
    return uname()[4]

def processor():

    """ Returns the (true) processor name, e.g. 'amdk6'

        An empty string is returned if the value cannot be
        determined. Note that many platforms do not provide this
        information or simply return the same value as for machine(),
        e.g.  NetBSD does this.

    """
    return uname()[5]

### Various APIs for extracting information from sys.version

_sys_version_parser = re.compile(
    r'([\w.+]+)\s*'
    '\(#?([^,]+),\s*([\w ]+),\s*([\w :]+)\)\s*'
    '\[([^\]]+)\]?', re.ASCII)

_ironpython_sys_version_parser = re.compile(
    r'IronPython\s*'
    '([\d\.]+)'
    '(?: \(([\d\.]+)\))?'
    ' on (.NET [\d\.]+)', re.ASCII)

_pypy_sys_version_parser = re.compile(
    r'([\w.+]+)\s*'
    '\(#?([^,]+),\s*([\w ]+),\s*([\w :]+)\)\s*'
    '\[PyPy [^\]]+\]?')

_sys_version_cache = {}

def _sys_version(sys_version=None):

    """ Returns a parsed version of Python's sys.version as tuple
        (name, version, branch, revision, buildno, builddate, compiler)
        referring to the Python implementation name, version, branch,
        revision, build number, build date/time as string and the compiler
        identification string.

        Note that unlike the Python sys.version, the returned value
        for the Python version will always include the patchlevel (it
        defaults to '.0').

        The function returns empty strings for tuple entries that
        cannot be determined.

        sys_version may be given to parse an alternative version
        string, e.g. if the version was read from a different Python
        interpreter.

    """
    # Get the Python version
    if sys_version is None:
        sys_version = sys.version

    # Try the cache first
    result = _sys_version_cache.get(sys_version, None)
    if result is not None:
        return result

    # Parse it
    if sys_version[:10] == 'IronPython':
        # IronPython
        name = 'IronPython'
        match = _ironpython_sys_version_parser.match(sys_version)
        if match is None:
            raise ValueError(
                'failed to parse IronPython sys.version: %s' %
                repr(sys_version))
        version, alt_version, compiler = match.groups()
        buildno = ''
        builddate = ''

    elif sys.platform[:4] == 'java':
        # Jython
        name = 'Jython'
        match = _sys_version_parser.match(sys_version)
        if match is None:
            raise ValueError(
                'failed to parse Jython sys.version: %s' %
                repr(sys_version))
        version, buildno, builddate, buildtime, _ = match.groups()
        compiler = sys.platform

    elif "PyPy" in sys_version:
        # PyPy
        name = "PyPy"
        match = _pypy_sys_version_parser.match(sys_version)
        if match is None:
            raise ValueError("failed to parse PyPy sys.version: %s" %
                             repr(sys_version))
        version, buildno, builddate, buildtime = match.groups()
        compiler = ""

    else:
        # CPython
        match = _sys_version_parser.match(sys_version)
        if match is None:
            raise ValueError(
                'failed to parse CPython sys.version: %s' %
                repr(sys_version))
        version, buildno, builddate, buildtime, compiler = \
              match.groups()
        name = 'CPython'
        builddate = builddate + ' ' + buildtime

    if hasattr(sys, '_mercurial'):
        _, branch, revision = sys._mercurial
    elif hasattr(sys, 'subversion'):
        # sys.subversion was added in Python 2.5
        _, branch, revision = sys.subversion
    else:
        branch = ''
        revision = ''

    # Add the patchlevel version if missing
    l = version.split('.')
    if len(l) == 2:
        l.append('0')
        version = '.'.join(l)

    # Build and cache the result
    result = (name, version, branch, revision, buildno, builddate, compiler)
    _sys_version_cache[sys_version] = result
    return result

def python_implementation():

    """ Returns a string identifying the Python implementation.

        Currently, the following implementations are identified:
          'CPython' (C implementation of Python),
          'IronPython' (.NET implementation of Python),
          'Jython' (Java implementation of Python),
          'PyPy' (Python implementation of Python).

    """
    return _sys_version()[0]

def python_version():

    """ Returns the Python version as string 'major.minor.patchlevel'

        Note that unlike the Python sys.version, the returned value
        will always include the patchlevel (it defaults to 0).

    """
    return _sys_version()[1]

def python_version_tuple():

    """ Returns the Python version as tuple (major, minor, patchlevel)
        of strings.

        Note that unlike the Python sys.version, the returned value
        will always include the patchlevel (it defaults to 0).

    """
    return tuple(_sys_version()[1].split('.'))

def python_branch():

    """ Returns a string identifying the Python implementation
        branch.

        For CPython this is the Subversion branch from which the
        Python binary was built.

        If not available, an empty string is returned.

    """

    return _sys_version()[2]

def python_revision():

    """ Returns a string identifying the Python implementation
        revision.

        For CPython this is the Subversion revision from which the
        Python binary was built.

        If not available, an empty string is returned.

    """
    return _sys_version()[3]

def python_build():

    """ Returns a tuple (buildno, builddate) stating the Python
        build number and date as strings.

    """
    return _sys_version()[4:6]

def python_compiler():

    """ Returns a string identifying the compiler used for compiling
        Python.

    """
    return _sys_version()[6]

### The Opus Magnum of platform strings :-)

_platform_cache = {}

def platform(aliased=0, terse=0):

    """ Returns a single string identifying the underlying platform
        with as much useful information as possible (but no more :).

        The output is intended to be human readable rather than
        machine parseable. It may look different on different
        platforms and this is intended.

        If "aliased" is true, the function will use aliases for
        various platforms that report system names which differ from
        their common names, e.g. SunOS will be reported as
        Solaris. The system_alias() function is used to implement
        this.

        Setting terse to true causes the function to return only the
        absolute minimum information needed to identify the platform.

    """
    result = _platform_cache.get((aliased, terse), None)
    if result is not None:
        return result

    # Get uname information and then apply platform specific cosmetics
    # to it...
    system,node,release,version,machine,processor = uname()
    if machine == processor:
        processor = ''
    if aliased:
        system,release,version = system_alias(system,release,version)

    if system == 'Windows':
        # MS platforms
        rel,vers,csd,ptype = win32_ver(version)
        if terse:
            platform = _platform(system,release)
        else:
            platform = _platform(system,release,version,csd)

    elif system in ('Linux',):
        # Linux based systems
        distname,distversion,distid = dist('')
        if distname and not terse:
            platform = _platform(system,release,machine,processor,
                                 'with',
                                 distname,distversion,distid)
        else:
            # If the distribution name is unknown check for libc vs. glibc
            libcname,libcversion = libc_ver(sys.executable)
            platform = _platform(system,release,machine,processor,
                                 'with',
                                 libcname+libcversion)
    elif system == 'Java':
        # Java platforms
        r,v,vminfo,(os_name,os_version,os_arch) = java_ver()
        if terse or not os_name:
            platform = _platform(system,release,version)
        else:
            platform = _platform(system,release,version,
                                 'on',
                                 os_name,os_version,os_arch)

    elif system == 'MacOS':
        # MacOS platforms
        if terse:
            platform = _platform(system,release)
        else:
            platform = _platform(system,release,machine)

    else:
        # Generic handler
        if terse:
            platform = _platform(system,release)
        else:
            bits,linkage = architecture(sys.executable)
            platform = _platform(system,release,machine,processor,bits,linkage)

    _platform_cache[(aliased, terse)] = platform
    return platform

### Command line interface

if __name__ == '__main__':
    # Default is to print the aliased verbose platform string
    terse = ('terse' in sys.argv or '--terse' in sys.argv)
    aliased = (not 'nonaliased' in sys.argv and not '--nonaliased' in sys.argv)
    print(platform(aliased,terse))
    sys.exit(0)